In recent years, supervision has started to be carried out such that each worker does not have a heat stroke by making each worker wear an electronic device which is called a wearable device and the like and acquiring information on each worker working in a worksite in summer.
For example, adjustment of a reference value for detecting a sign of a heat stroke depending on a working environment has been generally performed. However, an adaptive estimation of a body condition of each worker in consideration of a period following restart of a work after taking a break in which heat or the like largely affects a change in body condition, has not been performed.